1. Field of the Invention
The present invention relates to a radiation image capturing apparatus and a method of driving the same.
2. Description of the Related Art
Japanese Patent Laid-Open No. 2013-135390 has disclosed a radiation image capturing apparatus including a plurality of sensors configured to detect radiation and a readout unit configured to read out signals from the plurality of sensors. The plurality of sensors of the radiation image capturing apparatus include, in addition to an imaging sensor configured to perform radiation imaging, a monitor sensor configured to monitor an irradiating dose of radiation from a radiation source.
According to Japanese Patent Laid-Open No. 2013-135390, the signals are regularly read out from the monitor sensor during radiation irradiation and Auto Exposure Control (to be simply referred to as “AEC” hereinafter) of, for example, controlling the radiation source based on the signals is performed.
A control signal for reading out the signals from the sensors is supplied to the readout unit. For example, when reading out the signals from the monitor sensor, crosstalk may occur between a signal line which transmits the control signal and a signal line which transmits the signals from the monitor sensor, and a signal level from the monitor sensor may vary. The signal level from the monitor sensor may also vary by, for example, substrate noise caused by operating the readout unit. This may cause a decrease in AEC accuracy.